Project lead: Thomas DeBell
LoRa HUB Project
This project page will focus on the design, construction and future direction for the OPEnS Lab LoRa Hub receiver, primarily used for the Evaporometer.
- Receive and parse sensor data at a central hub for data retrieval
- Receive and parse remote sensor data and dynamically upload it to a google Spreadsheet
- Allow for insitu collection of data to better understand remote locations
- Allow for a cost effective, accurate and dynamic star network of sensors
- Provide real-time data for a variety of visulization applications
After months of prototyping, experimenting and redesigning, on July 27, 2017 I finally began to see the fruits of the OPEnS lab collective labor. we successfully deployed our first "fully open source" LoRa transmitter and receiver with near real-time updates to a Google Sheet. This deployment came after many weeks of collaboration between myself, Manuel Lopez, and Marissa Kwon on the data transmission protocol (outlined in the chart above) using the Adafruit LoRa 32u4 Feather board. Marissa and Manuel worked largely on integrating the different sensors on the transmitter side of things (Evaporimeter) and Chet and myself worked on the parsing, storing and LAN/SD logging of the data using the 32u4 feather in conjunction with the Adafruit Ethernet Featherwing (LoRa Hub).
The most demanding part of this process was coming up with a way of having a simple microprocessor (32u4 feather) open a secure gateway to log to a Google Sheet. However, we found out that this was impossible to do directly due to the nature of Google's security requirements and microprocessors limited handshake capabilities. However, by using a third-party Application Programming Interface, PushingBox, we were able to pass the byte data off and have the API doing the gateway heavy lifting and organizing using a modified Google Application Script in the Spreadsheet. The result of this somewhat tedious process has enabled the OPEnS lab to watch in near real-time the collection of over 100,000 data points in the past two months containing high precision sensor data, including data pertaining to the Great North American Eclipse.
- Reliable data transmissions from up to 2km away in heavy wooded conditions
- Battery optimized for up to 309 days of transmission
- Over 90,000 data points in the first two months of deployment
- 5-minute update interval gave near “real-time” updates
- Support for many data fields, in our case, Device ID, RTC information, Temperature, Humidity, Applied mass, Infrared Light, Full light spectra and Battery voltage.
As technology continues to develop, climate conditions continue to change and human kind continues to be curious, the need to develop wireless communication and networked data hubs are essential for expanding the viability and functionality of distributed sensor networks. This and other transmission protocols is currently being further developed for use in several other projects conducted by the OPEnS Lab. Deployment of a more robust hub, capable of supporting 20+ LoRa enabled devices, is set for deployment in early 2018.
DeBell, Thomas C. “Design and Deployment of a General Purpose, Open Source LoRa to Wi-Fi Hub and Data Logger (2017 AGU Fall Meeting).” 2017 Fall Meeting, American Geophysical Union , Oct. 2017, agu.confex.com/agu/fm17/preliminaryview.cgi/Paper221030.html.